Apparatus for making mold charges from plastic ceramic materials



7 Sheets-Sheet l A. J. WAHL FOR MAKING MOLD CHARGES APPARATUS FROM PLASTIC CERAMIC MATERIALS R O T N E V M w J M w A Jan. 10, 1950 Filed Feb. 12, 1945 Jan. 10, 1950 A. J. WAHL 2,494,112

APPARATUS FOR MAKING MOLD CHARGES FROM PLASTIC CERAMIC MATERIALS 7 Sheets-Sheet 2 Filed Feb. 12, 1945 Jan. 10, 1950 A. J. WAHL 4,

APPARATUS FOR MAKING MOLD CHARGES FROM PLASTIC CERAMIC MATERIALS 7 Sheis-Sheet 3 Filed Feb. 12 1945 INVENTOR Albert J PVa/EZ.

Jan. 10, 1950 A. J. WAHL 2,494,112

APPARATUS FOR MAKING MOLD CHARGES FROM PLASTIC CERAMIC MATERIALS Filed Feb. 12, 1945 7 Sheets-Sheet 4 INVENTOR 1416191 5 J Wa/z'l.

WXTTO R N Jan. 10, 1950 A. J. WAHL APPARATUS FOR MAKING MOLD CHARGES FROM PLASTIC CERAMIC MATERIALS 7 Sheets-Sheet 5 Filed Feb. 12, 1945 N mm INVENTOR Albefi J W257)! W%' AT%RNEY Jan. 10, 1950 A. .1. WAHL 2,494,112

APPARATUS FOR MAKING MOLD CHARGES FROM PLASTIC CERAMIC MATERIALS 7 Sheets-Sheet 6 Filed Feb. 12, 1945 m, o Q R 0 M g Q N. Kb q N INVENTOR BY J j ATTORVNEY Jan. 10, 1950 A. J. WAHL APPARATUS FOR MAKING MOLD CHARGES FROM PLASTIC CERAMIC MATERIALS 7 Sheets-Sheet 7 Filed Feb. 12, 1945 INVENTOR Albefit J W246i.

5 7 ATTORNE%- Patented Jan. 10, 1950 UNITED STATES P NT OFFICE Albert J. Wahl, Pleasant Hills, Pa., assignor to Miller Pottery Engineering Company, Swissvale, Pa., a corporation of Pennsylvania Application February 12, 1945, Serial No. 577,444

This invention relates to apparatus for making mold charges from plastic ceramic material in the manufacture of pottery dinnerware and the like. It has to do particularly with the automatic production, in successive order, of clay charges or blanks containing a uniform or substantially uniform volume of material, to be deposited on the molds of automatic dinnerware fabricating machinery and formed into pieces of ware.

It is highly desirable in the manufacture of all grades of dinnerware, both vitreous and semivitreous, by automatic machine, that the charges of clay or blanks from which the ware is made be of substantially uniform size and volume for a given production. If the blanks are undersize or contain a smaller volume of clay than an allowable minimum, the molding surface may not be entirely covered, or not covered to the required depth, and the piece will be defective because of the deficiency and have to be scrapped. If the volume of clay contained in the blank exceeds a predetermined allowable maximum, an excessive amount of scrap or waste clay will be produced. This reduces the ware yield from a given tonnage of clay and increases production costs because of the additional expense for reprocessing the scrap.

In preparing plastic ceramic material for fabrication, it is customary to mix the ingredients with water and thereafter remove some of the liquid by filter pressing. The solids are recovered in the form of large slabs or cakes of plastic clay which are mascerated and homogenized by pugging, and from this pugged material the mold charges or blanks are made. Some attempts have been made heretofore to employ a pug mill as a means for feeding a solid column of clay to a periodically operated cutting 01f implement in the making of charges or blanks of clay automatically. Pug mills are usually equipped with an auger which forces the clay through a restricted outlet and it is the extrusion from this outlet which is segregated into charges. While this is a very simple and direct method of forming charges, it has not proved satisfactory or successful because the rate of extrusion is not uniform and the volume of clay contained in successive charges constantly varies beyond allowable limits.

Because of this inherent and undesirable characteristic of a pug mill, the trend has been in automatic production toward feeding systems wherein the pug mill extrusion is cut on in long 4 Claims. (Cl. 25-22) operating independently of the pug mill, to the rolls or pugs that are fed by separate mechanism cutting off implement. increased the original cost for feeding equipment and has added to the expense of upkeep, maintenance and operation of automatic systems of production. To cite an example, one arrangement employs large capacity tubular magazines which are filled by the pug mill with clayand then manually detached and transported to a distant feed pipe and the contents pushed out through the pipe nozzle to a cutting wire by an hydraulically operatedram. The labor alone required to operate this system amounts to two or more men, and this does not take into account the labor required for maintenance and servic- 1ng. 7

It is among the objects of this invention to provide'for making charges or blanks of clay in which the volume of material contained in successive charges or blanks is not greater or less than allowable limits wherein a pug mill or the like is employed as a means of feeding the clay to a periodically operated cutting 01f implement, thereby making this most simple and direct method of charging molds both practical and suitable for use in connection with presentday automatic production machinery and eliminating the need for separate and costly clay feeding equipment. 7

Generally speaking, in accordance withthis invention, the pug mill is arranged with the extrusion outlet facing downwardly toward the mold at the feeding station of an automatic ware fabricating machine. The cutting operation under the extrusion outlet is synchronized with the operations of the fabricating machine, the cutting wire operating in synchronism with the mold indexing means to sever a charge of clay from the pug mill extrusion to be deposited on a mold therebelow. The movement of the extrusion auger of the pug mill is automatically controlled by the machine so as to force the same or approximately the same volume of material through the extrusion outlet during and 1 within each cycle of operation of the fabricating machine and the movement of the auger is arrested by other means during each machine cycle when the required volume of clay has been delivered and prior to the operation of the cutter.

- Other objects and advantageous features will be noted in the following detail description and accompanying drawings wherein like reference characters designate corresponding parts and wherein:

Figure 1 is a plan view of a were fabricating This has considerably" machine and pug mill in associated feeding relation therewith.

Figure 2 is a side elevation of the apparatus of Figure 1, with the lower half of the fabricating machine omitted, taken in the direction of arrows 22 of Figure 1.

Figure .3 is an end elevationof the fabricating machine of Figure 1 and the front end of the pug mill on an enlarged scale and illustrating in side elevation some of the clay segregating apparatus and mechanism for controlling the operation thereof.

Figure 4 is an end elevation-of the drive for the pug mill of Figure l taken iuthe direction of arrows 4-4 of Figure 1.

Figure 5 is a plan view of a modified form of 1 drive for the pug mill augers.

Figure 6 is a detail in side elevation of the mold transfer ring apparatus and associated mechanism.

Figure. 7 is a vertical section through the fabricating machine with some of the super structure omitted showing the Geneva drive for the.

of Figure 9 viewed from in front of the pug mill nozzle.

Figure 13 is a. detail illustrating how the segregating apparatus operates in severing slices of clay from the pug mill extrusion.

Figure 14 is a view showing in diagrammatic fashion how the operation of the cutter may be controlled by a photo-electric cell.

Figure 15 is a piping'and wiring diagram com.- bined illustrating the manner in which the entire apparatus is controlled.

Figure 16 is a detail of one of the timer discs and a fragment of a valve operating member.

With reference to Figures 1 and 2, l designates a pug mill and 2 a'potterywarefabricating machine. While any suitable form of pug mill may be employed, I have shown byway or example a type known as a dc-airing pug mill having a vacuum chamber 3 in which occluded air is removed from shredded clay to improve the workability of'the clay and for other reasons.

Said pug mill has a hollow barrel 4 provided with a filling opening 5 through which'filter'cakes are passed to the mascerating chamber. Inside the'barrel is an auger shaft 6 having masceratin blades 1 thereon to reduce the filter cakes to smaller size pieces and advance the material forwardly to the augerB, Figure 2, on said shaft. The ,augerforcesthe clay through a shredder (not'shown) into the vacuum chamber 3 where sub-atmospheric.pressure is maintained forthe purpose mentioned.

Clay is forced from the vacuum chamber by means of a lower'auger. In on shaft H, through a tapered passage into a delivery pipe l2, here shown as an elbow bolted to the nozzle flange l3 of,'.the pug mill, the lower or outlet end of the elbow being above and in vertical register with a nioldsupport 56, Figure 3, of the fabricating machine at what I shall call the feeding or mold charging station A of the machine.

The upper auger 8 and the lower auger It may be driven in unison and started and stopped at the same time or they may be independently driven and separately controlled with regard to stopping and starting and adjustment in the speed of rotation thereof. .The reasons for this will be hereinafter discussed.

,Thus as shown in Figures 1 and 2 shafts 6 and H are rotated by a common drive having a motor l5, variable speed transmission l6, V-belt drive ll, clutch i8, Figure 4, clutch shaft [9, sprocket 20 thereon and drive chain 2! which retates sprocket 22 on shaft 23 connected by a chain drive 24, Figure 2, to auger shaft H, and which also rotates sprocket 25, Figure 4, on shaft 26 to drive upper auger shaft 6 by gears 27 and 28, Figure. 1. Clutch 1% is provided with a pneumatic clutch control 29 and shaft l3 has a brake 30 thereon to be operated by an air cylinder 3|.

For rotating each shaft independently of the other, the drive of Figure 5 may be employed. In this form of drive, auger shaft 5 is driven by the same drive apparatus shown in Figure 1, however, shaft 23 which drives auger shaft H, is connected by sprocket chain 32 to clutch shaft 33 of an independent drive having a clutch 34, brake 35, V-belt drive 36, variable speed transmission 37 and motor 38. Thus each auger shaft may be controlled independently of the other.

The fabricating machine may, for example, comprise a frame 39 having a conveyor 40 for bringing empty molds in single file to a transfor point B, Figures 1, 3, 6, 7 and 8, where they enter the open fork d3 of a reciprocable transfer apparatus to be carried thereby to the feeding station A. Said apparatus comprises a pair of spaced, parallel, vertical supports 44 and 45 pivoted at their lower extremities to the machine frame and connected across the top by a frame 46 to which transfer said fork 43 and another one 47 are attached. The supports 44 and 45 are caused to reciprocate back and forth by a cam 48 on main cam shaft 49 and return spring 56,. the supports being guided in their back and forth movement by rollers 54 which roll in a horizontal guideway 55.

.Fork 43, carries a mold from the conveyor 40 to a position directly over a hollow ring chuck 56, smaller in diameter than the fork 43 so as to pass therethrough, which is directly below the outlet end of pipe l2 and is supported, Figures 6 and 8, in an offset position on a post 53 socketed in the ipress crosshead 59 in rear of the chuck. The

press crosshead 59 is raised and lowered on guides 60, Figure 8, by a cam Bl fixed on cam shaft 49 and spaced from cam 48. Thus when chuck 55 is elevated, the tang of the mold seats in. the ring chuck 56 and it is. lifted from the fork 43' where it is supported on the flare 62 and is carried up wardly to the outlet of pipe I2.

After the mold has been charged with clay in a manner to be hereinafter described, the chuck 56 is lowered by cam l'il into the other fork 41 of the transfer which has been moved to the right by cam 48 during the interval when the charge of clay was being out off and deposited on the mold. When the transfer moves to the left again the charged mold is carried to a position directly over another ring chuck 63, mounted on a post 58 carried by crosshead 59.

Chuck 63 lifts the mold out of fork 41 and holds it in raised position until the fork 41 again moves to the right and the end seat 64 of a mul- 5. tiple seat transfer 65, Figures 1 and 8, slides on rollers 66 into position therebelow. Transfer 65 is moved back and forth by a drum cam 61, Figure 1, on main cam shaft 49. When end seat 64 is below chuck 63, the chuck is lowered by cam 6| to deposit the mold in said seat. This multiple seat transfer carries the charged molds to a pressing position C where the clay is spread over the ware forming surface of the mold by a die 68 and then to a jiggering station D where the mold is rotated relative to a profile tool 69 to finish the back or interior of the article as the case may be, and then the mold is carried to' a conveyor I9 and deposited thereon to be transported to a dryer.

, Conveyors 49 and 19 are intermittently moved by a Geneva drive, Figure "I. Said drive comprises a disc ll fixed on cam shaft 49 having a roller I2 which successively enters the slots of the Geneva gear I3 thereabove fixed on shaft I4 journaled in the machine frame, Figure 6, to which a gear 15, Figure 6, is fixed that meshes with a pinion 16 on shaft 11; shaft 11, Figure 7, is connected by a sprocket chain I8 with a sprocket on shaft 19 that drives conveyor 49 by means of gears 89 and 8|, the latter gear being fixed on shaft 82 having a sprocket 83 thereon in driving association with the underside of the conveyor 49. Chain I8 also drives conveyor I9, but in the opposite direction, by shaft 84 and sprocket 83, Figures 1 and 7.

, The main camshaft 49 of the fabricating machine is driven by a motor Figure 1, through reduction-gearing enclosed in housing 52 including a clutch (not-shown) to be manually actuated to start and stop the machine.

,So much for the fabricating machine per se. It will suffice to say that the various moving parts of the apparatus just described are operated in synchronous fashion, so as to remove molds from conveyor 49 and index them from station to station until they are finally deposited on conveyor I9 with the formed ware thereon. Other forms of fabricating machine may, if desired, be substituted for the one described, for instance, an intermittently operated table type machine wherein the molds would be carried in a circular path through the fabricating zone.

The charge segregating apparatus, Figure 2, is disposed below the outlet end of discharge pipe I2 in position to sever charges of clay from the extrusion that issues therefrom and is supported by the frame 86 on which the pug mill is supported above the floor.

Said segregating apparatus comprises a cutter frame 88, Figures 10 and open at one end and having a cutting wire 89 detachably suspended across the open end between posts 99 and BI and angling rearwardly from side to side, the wire being tensioned by a spring 92 on post 9|. The closed end of the frame has a center hole through which the threaded end of piston rod 94 of air cylinder 95 projects and is secured thereto by nut 96. a

Air cylinder 95 comprises a front cylinder head 91 havinga bushed hole therein for receiving the piston rod 94 and a groove around the hole in whicha tubular sleeve 99 is seated. The rear cylinder head I99 also has a bushed hole therein for receiving the plunger and a groove around the hole to receive the opposite end of the tubular sleeve 99. The assembly thus described is held together by a plurality of tie rods I92 that are threaded into tapped holes in cap 91 and project through holes in cap I99 which is tightened against the sleeve 99 by nuts I93 thereon.

-The piston rod 94 has a plunger I94 fixed thereon to be moved in one direction by air entering the piston chamber I95 through a bore I96 in the front cap to thereby retract the cutter frame after 'a segregating operation. The piston and cutter frame are moved in the opposite direction on the cutting stroke by air under pressure entering the opposite end of the piston chamber through a bore I91 in rear cap I99.

To prevent the cutter frame from rotating about the axis of the piston rod, it is guided in its forward and reverse movement. For this purpose, the front cylinder head 91 is formed with a lateral extension which is slotted out as at I98 and wear plates I99 fastened to the top and bottom of the slot. One of the side members of the cutter frame is extended rearwardly as at H9 and is received in the slot and, as the frame moves back and forth the guide extension II 9 slides'freely in the slot and prevents the frame from turning.

The under surface of the front cap 91 is faced off to provide a level, smooth surface which rests on a plate III of Figure 9, fixed to the end of a piston rod II2 forming part of an air cylinder assembly I I3 supported therebelow in vertical position on a bracket H4 attached to the pug mill frame. The purpose of this air cylinder is to lower the cutter frame at the end of the cutting stroke so that the cutting wire may be pulled back without danger of interference with the stub of clay projecting from the outlet of pipe [2. The air cylinder assembly 95 is supported in such manner as to provide for this movement by welding to the rear cylinder head I99 a tubular extension II5, Figure 11, closed at the end by a plate II6 to which a long hollow bearing 1, Figure 10, is secured. This bearing is attached to a support I I8, secured to the pug mill frame, by a horizontal connecting pin I29 fixed in place to thereby provide for a pivoted connection allowing the air cylinder and cutter frame to be angularly moved in a vertical direction about this point as an axis. The piston rod 94 extends rearwardly through cylinder head I99 into the tubular extension '5. Angular movement of the cutter frame is regulated by an adjusting screw II6, Figure 9, above the air cylinder 95 supported by a bracket III' secured to the nozzle flange of the pug mill, Figure 9.

To regulate the extent of forward movement of the cutter frame, stop rods I2I one on either side of the air'cylinder are attached to the rear of the cutter frame by bolts I22, Figure 11. When the frame is moved forward, the adjusting screws I23 in the up turned ends 124 of these rods engage the rear face of cylinder head 91 and prevent further forward movement of the cutter frame. The extent of forward travel of the frame may be adjusted by said screws. The mechanism for operating the cutter in timed relation with the other apparatus hereof will be discussed later on in this description.

It is contemplated herein that the extrusion from the pug mill be arrested either by stopping it entirely or by appreciably slowing it down whilst a charge is being segregated therefrom. I propose to arrest the extrusion from a de-airing pug mill by stopping or slowing down auger I9 which forces the clay through the outlet of pipe I2 with or without discontinuing the feeding of clay into the vacuum chamber 3. Since the invention contemplates the use of pug mills other line I8I to control the pug mill by hand in case of emergency.

Simultaneously with the operation of valve I66 or just prior to the operation thereof, pin I55 on timer disc II moves lever I58 to the right to actuate valve I91 thereby disconnecting pipe I83 leading to the air cylinder 3| associated with brake 38 on shaft I9, Figure 1, from the main air line I80 and connecting pipe I83 to atmosphere through vent I 84 in valve I61, Figure 15. This releases the brake on shaft I9 so that the shaft will be free to turn as soon as the clutch I! is engaged.

During the operation of the pug mill it is preferred that the volume of clay fed into the vacuum chamber 3 is substantially equal to the volume of clay issuing from the outlet of pipe I2. The lower auger I8 is preferably operated in what is called a starved condition wherein the auger is only partly covered with shredded, deaired clay, and the vacuum chamber therefor, is consequently only partly filled with material. I have found that by operating the auger in this condition, the variations inthe rate of extrusion are not as great as they would be otherwise.

After the clay has extruded through the outlet of pipe I2, a predetermined distance, the leading end of the column strikes control plate I48 and depresses the plate against the tension of the spring I43. This trips plunger I3! associated with switch I38 and energizes circuit 185 thereby energizing solenoids I69 and I'll, Figure 15. When solenoid I69 is energized, lever I68 is pulled to the left thereby opening valve I88 and venting line I8I to atmosphere through vent I86, and simultaneously therewith valve I6? is closed to connect line I83 with the main air pressure line I80 to set brake 38. These operations arrest further extrusion of clay through the outlet of pipe I2.

The time required for each extrusion cycle may vary as between cycles due to the variation in the rate of extrusion. However, the maximum interval of time required to extrude a desired volume of clay may be determined in advance for any given size and volume of clay charge, and this maximum interval may be timed to start so that it Will end prior to the time of operation of the cutting wire 89. This may be accomplished by providing an auger of the proper size and number of wings to produce the required extrusion, and by rotating it at the proper speed to deliver the required amount of material. Thus, in the cycle of operations and after or at substantially the time the extrusion is arrested, pin I55 on timer disc I49 pushes lever I58 to the right, Figure 15, thereby actuating valve I65 and connecting line I8'I with line I88 leading to the main air pressure line I88. This causes the piston in air cylinder 85 to be moved to the left thereby cutting through the extrusion, Figure 13, to segregate a charge of clay I98 from the dependent column, the charge falling onto the molding surface of the mold which preferably has reached the highest point of elevation, although the charge may be cut off as the mold is being lifted up to charge receiving position, or as the mold is being lowered.

When roller I4? on the end of cutter frame 88 engages member I48, frame I34 is pushed to the left and as soon as the control plate M8 is dis engaged from the extrusion, spring I4 3 pulls the control plate upwardly thereby causing the plunger on switch I31 to be actuated, which de energizes circuit I85, Figure 15, thereby de-energizing solenoids I69 and I'II.

10 After the cutter 88 has completed the cutting stroke, Figure 13, pin I55 on timer disc I I'I,

moves lever I58 to the right thereby actuating valve I63 to disconnect line I92 from main air 5 line I80 and connect line I92 to atmosphere through vent I93. The weight of frame 88 depresses the plunger in air cylinder H3, Figure 9, and permits the frame 88 to swing downwardly on its pivot thereby moving the cutting wire 89 away from the projecting end of the extrusion so as not to interfere therewith upon the return stroke of the cutter.

After the cutter has dropped down, pin I55 on timer disc I48 moves lever I58 to the right thereby actuating valve IM to connect line I94 with main air line I 88 thereby reversing the movement of the piston in air cylinder 95 to cause the retraction of the cutter. Just prior to the actuation of valve I64, valve I65 is actuated to connect air line I81 with atmosphere through vent I95. Upon retraction of the cutter, pin I55 011 timer disc I41 moves lever I58 to the left thereby actuating valve I63 and connecting line I92 with the main air line I88. This causes the air cylinder II3 to again raise the cutter frame 88 to cutting level.

The cycle of operation just described, with regard to the extrusion of clay and the cutting off of the material and the return of the cutter to initial position, takes place within one complete cycle of operations of the fabricating machine and in this connection, after the mold 62 is charged with clay, the mold is lowered and deposited on the fork 41 of the transfer frame to be carried to the next station in a manner and for the purpose hereinbefore described.

Thus during each machine cycle the pug mill is started and stopped and the cutting wire is actuated to segregate a charge of clay. It has been stated herein that the extrusion auger of the pug mill could be appreciably slowed down rather than completely stopped during the segregating operation. This could be accomplished with the apparatus disclosed by merely slowing down the auger shaft by means of the brake 38 and by partial release of the clutch FL Moreover, the extrusion auger shaft 6 may be controlled insofar as stopping or starting or slowing down is concerned whereas, the upper auger shaft 6 may, if desired, be permitted to run continuously.

The drive shown in Figure 5 could be employed to accomplish this purpose in a perfectly obvious matter. Also, if desired, theupper shaft 6 and the lower shaft I0 may be operated and controlled independently of one another where it is desired to vary the rate of feed of shredded clay into the vacuum chamber.

Figure 14 illustrates how the operation of the pug mill may be controlled by means of a photoelectric cell. In this connection, photo-electric cell elements 208 and 28I are arranged so as to project a light beam across the path of travel of the extrusion at a given level. When the extrusion interrupts the beams, a circuit 202 is energized to cause the energization of solenoids I 89 5 and III for purposes herein before specified.

I claim:

1. The combination with a pottery fabricating machine having means for moving a series of clayshaping molds to and from clay-feeding and clayforming stations at uniform intervals, of a pug mill having a discharge outlet, a laterally closed v conduit extending from said discharge outlet to said feeding station and provided adjacent to the latter with a delivery orifice, a driven rotatable impeller in said pug mill for moving clay therefrom; and; through: said: conduit and extr ing it,in.;co1umn form iromxsaicli orifice; a. movable cLi-ttenfor removingv fIOIlh-Sgiidi column; of clay a slice thereof in. an amount: su-fiicient. to form a piece-of potterywaite without excessiee-waste, and means for stoppingthe-rotation. of said impeller and: as, a consequence thereof: the; extrusion: of clay from said orifice, said: means including, as an element. thereoiti an; actuatondisposed bey the clay-cutting pathofmovement of said cutter andin the pathrof movement (Bf-(0116; extruded clay and being responsive to the movement of the outer end of such day, wherebvthe thickness of each slice of: clay is determined by the spacing of; said actuator from the clav cutting path of movement: of. said cutter:

2. The; combination. with a potteryfabricating machine having: meansfor. moving a series .of clayshaping molds to and. from clay-feeding. andaelayforming stations at uniform: intervals, of a pus mill having a discharge outlet, a laterally closed conduit extending from said dischar e outlet-'1 to said feeding station: and: piiovidedi adjacent to the latter with a delivery; onificaa driven rotate able impeller in said pug. mill for moving clay.

therefrom. and through: said} conduit; and extruding itin columnl formirom: saiclzorifice; a. movablecuttei for removingaf-nomsaid; column of; clay a, slice thereof.- in an amount. sufficient to, form; a; piece. oft'potteryware Without excessive Waste v and. means for stopping the rotationrof said; impelle and as. a, consequence thereof the extrusion, of, clay. from said: orifice, said means; including; as an. elementthereof: an: electric actuat r, havin a switch-controlling:member:disposed; beyond-the clay-cutting. path of movement; of; said: cutter; and in the athotmovementof: the-extnudediclav; nd; movable by. the: movement of: the-outer end, of such clay, whereby: the. thickness: o c Sliceof? clay is determined-iby the: spacing of said switchecontrollingmemberfrom the; clayrcutting path of: movementot said. cutter.

3?. The combination. Wjthi a pottery fabricating machine having means formoving a. seriesofcla-v-shapingmolds toand tramway-feeding, and; clay-forming stations at uniform, intervals of. apug: milll having a discharge outlet. a. laterally closed; conduit ext-endingfrom said dischange'outlet to-said feeding station and provided adjacent to.thedatterv with a. horizontally-disposed orifice or-delivering clay downwardly, a drivenirotatable impeller in-,saidpug mill! for'moving. clay therefromandthrough s'aidconduit and extruding.- it: downwardly} in pendant, column form thorn, orificel. a horizontally" movable cutter. for remov-- ing from said column of clay a slice. thereof: in: an amount-.suflieient toior-m-a piece of potterywarewithout excessive waste, and means for s ep ping. the, rotation of saidimpeller and as a 001156.? quence thereofthev extrusion. of; clay from said orifice, said means including. as an element there ofan actuator disposed below the clay-cutting; path of.. movement of said. cutterandin. the path off movement. of, the exttuded. clay and. being. re sponsive. to the downward, movement. of, the? outer.

end, of; such clay; whereby; the; thickness of: each slice of clay is determined by the spacing of said actuator from. theclay-cutting path of. movement ofsaid-cutten.

4-. The-combination with a pottery fabricating machine having, means for moving a series of clay-shaping. molds tozand' from clay-feeding and clay-forming stations at uniform intervals, ofa pug mill having, a dischange outlet; a later-ally closed conduit extending from said. dischargeout.- lotto said feeding station and provided adjacent to thelatter with. a horizontally disposed. orifice for delivering clay downwardly, a driven. rotate able imnellerin said pugmill for moving clay therefromand; through saidconduit and; extrud= ing it downwardly inpendant Qolumh forml from said onifice, a. horizontally. movable cutteriorr re; moving from said column of clay a slice thereof in-an amount suflicientto form-a pieeeof patternware withoutexcessive waste and-means for $1109? ping. thev rotation, ofsaid. impellen and: as aconsea quence. thereof: the. extrusion of; clavfromsaid. orifice, said means including, as an.- element thereofv an electric actuator having-a. switchrcontrolling member. disposed; below the clay-cutting path 013 movement of said cutter and in thefpath of movementof the extruded. clay andmovable by; the downward. movement of the; outenend ofsuch, clay, wherebythe thickness ofeach, slice of clay.

. is determined by. the spacingof, said SWitIChF-COD- trolling member from. the. clay-cutting. pathofmovement of said cutter: V g

J,-. WAHL.

REFERENCES CITED:

The following; references are of:' record in thefile on this: patent:

UNITED STATES PATENTS Number Name Date Re. 20,401 Miller F June-'8; 1937 1,800,324: Shipley- APB. 14,1931;- 1,811,412 Whitacre- June'23 1:93;1-. 1,842,622 Miller J an: 26,, 1932 1,931,371 Bonnat i h- OGL'. 17,.1=933; 1944 464 Richardson Janz.23,.1:934; 1,989,038 Brown Jan, 22, 1935; 2,015,855 Kerr- Oct; 1, 1935i 2,051,781 Brown" M Aug. 18, 1.936. 2,054,476;- Derry et a1. Sept. 15', 1,936; 2,078,565 Durst etaal Apr. 2S, 1 93?]; 2,109,028- Miller Feb; 22; 1938: 2,204,513 Sandburgetal; June 11, 1940; 2,204,532 Erbguth et a1; June 11, 1940 2,278,513 Emerson Ap17 7;; 1.9423 2,301,906 Miller ,Nov:. 10, 1942: 2,310,859 Miller Feb. 9;. 119%: 2 ,348,197 Ernst et al. May'9; 194.4% 2,356,496 Avenhaus Aug. 22; 1944'- 2,389,163 Miller Nov. 20'; 1945:

FOREIGN PATENTS Number Country Date 412,248 Great. B !1itain-, June 125, 19.341 160,785- GreatBritain Feb; 4, 1:937 

